Satellite Navigation: GPS Modernization and R&D in the ...gauss.gge.unb.ca/papers.pdf/csa.nsts2001.pdfGeodetic Research Laboratory • Department of Geodesy and Geomatics Engineering

Geodetic Research Laboratory • Department of Geodesy and Geomatics Engineering • University of New Brunswick

RBL/NSTS30 Jun. 01

Satellite Navigation:GPS Modernization and R&D in

the Academic Sector

Richard B. Langley

National Sector Team for Space Annual Meeting, Canadian Space AgencySt-Hubert, QC. • 3-4 July 2001

Geodetic Research LaboratoryDepartment of Geodesy and Geomatics Engineering

University of New BrunswickFredericton, N.B.


RBL/NSTS30 Jun. 01

Outline

• GPS Weaknesses

• GPS Modernization

• The Shrinking GPS Receiver

• GPS and E-911

• The Future of GPS Technology

• GPS R&D at Canadian Universities


RBL/NSTS30 Jun. 01

GPS Weaknesses

• C/A-code only on L1: no dual-frequency ionosphericdelay correction

• L1 and L2 signals not afforded total spectrum protection• GPS signals relatively weak (actually buried in

background noise)- Signals cannot readily penetrate into concrete and

steel buildings or underground- Signals can be blocked by buildings and other

structures- Susceptible to interference or jamming

• Reflected signals (multipath) cause position error


RBL/NSTS30 Jun. 01

Signal Blockage

Tall buildings can blockGPS satellite signals

Reduced satellite visibilityincreases geometrical

dilution of precisionresulting in reduced

positioning accuracy


RBL/NSTS30 Jun. 01

GPS Modernization

• One goal is enhanced capabilities for civil users of GPS

• Civil benefits include:

– Selective Availability (SA) turned off on 2 May 2000

– Second civil frequency for ionospheric correction andredundancy

– Third civil signal for “safety of life” applications inprotected spectrum; more robust; also provides highaccuracy and benefits real-time applications


RBL/NSTS30 Jun. 01

Selective Availability Switched Off


RBL/NSTS30 Jun. 01

GPS Modernization Details

• Last 12 Block IIRs - Add second civil signal (C/A on L2)and new military signal (M-code). Provide more signalpower.

First modernized launch (Block IIR-M) - FY03

• First 6 Block IIFs (“IIF Lite”) - All of above capabilitiesplus new third civil signal in protected band (L5).

First Block IIF “Lite” launch - FY05

• At the current GPS satellite replenishment rate, all threecivil signals (L1-C/A, L2-C/A, and L5) will be available forinitial operational capability by 2010, and for fulloperational capability by approximately 2013.


RBL/NSTS30 Jun. 01

Block IIR Satellite


RBL/NSTS30 Jun. 01

Block IIF Satellite


RBL/NSTS30 Jun. 01

Signal Modernization

1227 MHz 1575 MHz1176 MHzL2 L1L5

P(Y)P(Y)

C/AC/A

P(Y)P(Y)

C/AC/A

P(Y)P(Y)

P(Y)P(Y)

C/AC/A

P(Y)P(Y)

C/AC/A

P(Y)P(Y)

C/AC/AMM MM

Present Signal

Civil Non-AviationSignal (>2003)

Civil Aviation &New MilitarySignals (>2005)


RBL/NSTS30 Jun. 01

The Incredible Shrinking GPS Receiver

• First commercially availableGPS receivers, circa 1980, consisted of two 19-inch racksof electronics

• In 1982, first “portable” receiverintroduced; weighed 25 kg andconsumed 110 watts of power

• First large handheld receiversintroduced in 1988

• 1993: multi-chip module prototype

• 1999: GPS watch


RBL/NSTS30 Jun. 01

“Two Chip” GPS Receiver


RBL/NSTS30 Jun. 01

AxiomNavigation Swift B1 OEM Receiver

• OEM module

• Based on SiRF 2ndgeneration chipset


RBL/NSTS30 Jun. 01

iTrax02 GPS Receiver Module

|----------25 mm---------|

|----

----

--25

mm

----

----

--|


RBL/NSTS30 Jun. 01

Casio Satellite Navi Watch

• PAT-1GP first generationversion introduced in1999

• PAT-2GP second generation versionintroduced last year

• More compact and lighter

• Rechargable lithium-ionbattery

• PC interface

• $499.95 (U.S.)


RBL/NSTS30 Jun. 01

FCC E-911 Requirements

• FCC issued a Report and Order in October 1996 requiringU.S. network operators to implement an E-911 locationcapability by October 2001

• Phase I: Pass caller’s phone number, cell-site, and cell-sector location information to public safety answering point(PSAP) by April 1998

• Phase II: Provide caller’s location (latitude and longitude)to appropriate PSAP by October 2001 – automatic locationidentification (ALI)

• 2 major solution technologies: network-based andhandset-based


RBL/NSTS30 Jun. 01

Networked-based Location Technologies

– provides the location of wireless 911 callers usinghardware and/or software in the wireless network and/oranother fixed infrastructure

– does not require the use of special location determininghardware and/or software in the caller’s portable or mobilephone

– e.g., time-difference of arrival (TDOA), angle of arrival(AOA), hybrid systems, RF “fingerprinting”


RBL/NSTS30 Jun. 01

Handset-based Location Technologies

– provides the location of wireless 911 callers using speciallocation-determining hardware and/or software in thecaller’s portable or mobile phone

– may employ additional location-determining hardwareand/or software in the wireless network and/or anotherfixed infrastructure

– e.g., GPS, Loran-C

– GPS: standalone and network-assisted (e.g. SnapTrack)


RBL/NSTS30 Jun. 01

Phase II Accuracy Standards

• For network-based solutions: 100 metres for 67% of calls;300 meters for 95% of calls

• For handset-based solutions: 50 metres for 67% of calls;150 metres for 95% of calls


RBL/NSTS30 Jun. 01

GPS-capable Handsets

• First sets introduced in 1999

• Several manufacturers currently selling GPS-equippedhandsets, mostly in Europe (GSM)

• SiRF Technology recently signed major contracts withboth Nokia and Ericsson


RBL/NSTS30 Jun. 01

The Future of GPS Technology

• Further miniaturization of the technology

• Integration of GPS receivers into PDAs, cameras, sportsequipment, etc., etc.

• Pet, child, and disabled tracking systems and services

• Other location-based services such as L-commerce

• Network-assisted GPS (permits weaker signal use)

• Bluetooth (short range RF) connectivity between GPSreceivers and other Bluetooth-equipped devices(GPS + Bluetooth = positioning inside buildings?)

• New GPS signals; higher power signals

• GPS + GLONASS + Galileo


RBL/NSTS30 Jun. 01

GPS R&D at Canadian Universities

• Main research labs:– Geodetic Research Laboratory, Dept. of Geodesy and Geomatics

Engineering, University of New Brunswick (Langley, Santos,Dare)

– Satellite-based Positioning and Navigation Group, Dept. ofGeomatics Engineering, The University of Calgary (Lachapelle,Cannon)

– Equipe GPS, Centre de Recherche en Géomatique, UniversitéLaval (Santerre)


RBL/NSTS30 Jun. 01

University GPS R&D Themes

• Physical and mathematical modelling of GPS observables(both functional and stochastic models)

• Development of new techniques and procedures for GPSpositioning and navigation and the enhancement ofexisting techniques

• Assessment of accuracy and integrity of positionalinformation


RBL/NSTS30 Jun. 01

University of New Brunswick

• Modelling the neutral-atmosphere propagation effects inradiometric space techniques

• Improved modelling of data from the Western CanadaDeformation Array

• Development of a low-cost GPS-based vehicle trackingsystem

• Automatic daily assessment of the GPS broadcastephemerides

• Automatic daily assessment of WAAS corrections andWAAS performance in eastern Canada

• Development of precise point positioning algorithms andsoftware


RBL/NSTS30 Jun. 01

University of New Brunswick, cont’d.

• Geometric tracking of GPS-equipped low earth orbiters

• Automated cycle slip correction

• Stochastic modelling of GPS observations

• Improvement of precise and reliable kinematic GPSpositioning in real time

• Optimal techniques for GPS ambiguity resolution

• Development of multipath mitigation techniques

• Ionospheric effects on Galileo

• Establishment of reference sites and control networks

• GPS equipment and site testing


RBL/NSTS30 Jun. 01

The University of Calgary

• Availability, reliability and accuracy of GPS/Galileo

• Estimation of oscillator stability in the time domain usingGPS

• GPS/INS integration

• Use of multiple GPS antennas/receivers for code andcarrier phase multipath mitigation

• Vehicular navigation in urban canyons and under forestrycanopy

• Use of multiple reference stations for GPS carrier-phasebased positioning

• Centimetre-level relative positioning of distributed movingplatforms


RBL/NSTS30 Jun. 01

The University of Calgary, cont’d.

• Availability and reliability of GPS augmented with othersatellite systems and onboard sensors

• Use of GPS/INS for aircraft positioning

• Use of combined GPS and GLONASS for heading andpitch determination

• Effect of the ionosphere on GPS in auroral regions

• Effect of ice loading on GPS antennas

• Augmentation of GPS with pseudolites

• GPS-based attitude determination using a multi-antennaapproach

• Application of GPS and GIS technologies to precisionfarming


RBL/NSTS30 Jun. 01

Université Laval

• Improvement of kinematic OTF-GPS positioning over longdistances

• Integration of GPS/GLONASS satellite positioning systems

• Improvement of GPS ambiguity resolution using heightconstraint for bathymetric surveys

• Simulations of attitude determination for RADARSAT-Iusing GPS

• Direct determination of angular velocity using GPS

• A combined method for GPS ambiguity resolution withsingle frequency receivers

• Development of a GPS-based system for the support of shipberthing operations


RBL/NSTS30 Jun. 01

Université Laval, cont’d.

• Use of GPS for bridge deformation monitoring

• Impact of antenna configuration on GPS attitudedetermination

• Development of a telescopic mast for a GPS antenna

• Modelling ionospheric effects for ambiguity resolution

• Use of GPS in large engineering works

• Use of GPS for precision agriculture

• Combined use of GPS and RADARSAT imagery fordeformation monitoring

• Use of GPS in sport


RBL/NSTS30 Jun. 01

Back-up slides


RBL/NSTS30 Jun. 01

Garmin NavTalk

• Garmin Corporation, Olathe, KS

• NavTalk Pilot: first GPS-equippedcellular telephone (1999)

• Advanced Mobile Phone System

• Moving-map display

• First Assist™ one-touch emergencyservice

• Standard version (NavTalk) alsoavailable

• NavTalk II GSM phone (4th Q, 2001)


RBL/NSTS30 Jun. 01

Tendler Cellular FoneFinder

• GPS receiver add-on to conventional cellular phone

• Emergency button

• Position information sent in synthesized voice announcement


RBL/NSTS30 Jun. 01

Airbiquity GPS Accessory

• Airbiguity Inc., BainbridgeIsland, WA

• Adds GPS capability to existingNokia 5100, 6100, and 7100series phones

• 12-channel, SiRF chip set basedAxiom GPS receiver built intophone battery pack

• Single button transmission ofposition

• Data port for Palm OS PDAs


RBL/NSTS30 Jun. 01

Benefon Track GSM+GPS Phone

• Benefon Oyj, Salo, Finland

• Professional telematics phone

• GSM phone + GPS

• 12-channel (all-in-view) GPSreceiver

• Flip-up GPS antenna

• Short Message Service

• Mobile Phone Telematics Protocol

• Emergency dialing


RBL/NSTS30 Jun. 01

Benefon Esc! Personal Navigation Phone (1)

• Benefon Oyj, Salo, Finland

• Personal navigation phone

• GSM phone + GPS

• 12-channel (all-in-view) GPS receiver

• Flip-up GPS antenna

• 100 x 160 pixel screen

• Map display

• External antenna and NMEA connectors


RBL/NSTS30 Jun. 01

Benefon Esc! Personal Navigation Phone (2)

• Personal organizer

• E-mail and Web access

• Short Message Service

• Mobile Phone Telematics Protocol

• Mobile Map Service Protocol

Documents

Satellite Navigation: GPS Modernization and R&D in the ...gauss.gge.unb.ca/papers.pdf/csa.nsts2001.pdfGeodetic Research Laboratory • Department of Geodesy and Geomatics Engineering